<!DOCTYPE>
<html>
<head>
<meta charset="utf-8">
<title>  打开百度</title>
<style>
a:link {color:black}
a:visited {color:red}
a:hover {color:blue}
a:active {color:green}
</style>
</head>
<body>
<a href="http://www.baidu.com" target=_blank">这是百度的链接</a>
</body>
</html>